Contrast Enhanced Transrectal Ultrasonography (TRUS) to Assess Prostatic Vascularity After Radiotherapy (XRT)

Solid tumors, including prostate cancer, commonly exhibit tumor-associated neovascularity (growth of new blood vessels to feed the tumor) with increased microvessel density. Systemic, hormonal, and radiotherapy treatments typically decrease or suppress tumor - associated vascularity through several mechanisms, including apoptosis (process of cell death) and anti-angiogenic pathways (ways to destroy new blood vessel growth). Previously at the investigators' center, they have demonstrated that increased prostatic vascularity (blood vessels defined to prostate) detected ultrasonographically correlated with disease free survival after radical prostatectomy (surgical removal of entire prostate), and may be indicative of higher grade, higher stage disease. The significance of prostate neovascularity in response to treatment with external beam radiotherapy (EBRT) (standard of care) has not been well studied. The investigators hypothesize that prostate cancer that recurs after radiotherapy may exhibit measurable patterns of tumor-associated vascularity, which may represent a minimally invasive marker of cancer stage, grade and response to treatment. The investigators propose a pilot study to assess the feasibility of serial enhanced transrectal ultrasonography (TRUS) examinations during and after radiotherapy for prostate cancer.

Sex

Male

Minimum age

40 Years

Maximum age

80 Years

Inclusion Criteria:

* Men aged 40 - 80 years old
* Biopsy proven intermediate/high risk clinically localized prostate cancer, as determined by a Gleason score of 7 or higher, clinical stage T2b or higher, or PSA \> 10. Pathology will be confirmed by at least two reviews
* Patients opting for EBRT (external beam radiation therapy, standard of care) without hormonal ablation
* Ability to undergo serial TRUS procedures
* Ability to give informed consent

Exclusion Criteria:

* Subject has known hypersensitivity to octafluoropropane.
* Evidence of distant metastatic disease on staging evaluation
* Previous treatment for prostate cancer, including any form of androgen ablation
* Previous procedures involving the anus or rectum, making serial TRUS difficult or dangerous
* Expected life expectancy less than 10 years
* Baseline testosterone \< 200 ng/dL
* Subject with cardiac shunts and elevated pulmonary hypertension
* Subject has worsening or clinically unstable congestive heart failure.
* Subject has acute myocardial infarction or acute coronary syndrome.
* Subject has ventricular arrhythmias or is high risk for arrhythmias.
* Subject has respiratory failure, severe emphysema or pulmonary emboli.
* Subject has a history of cardiac shunt or pulmonary hypertension.

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